Hair-spring stud for watches



E. RIVETT. Hair-Spring Stud for Watches.

No. 224,227. Patented Feb. 3,1880.

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Figs v INVEIJT IR WITNESEEE awwxbqw @Z MM/ UNITED STATES PATENT OFFICE.

EDWARD RIVETT, OF BOSTON, MASSACHUSETTS.

HAIR-SPRING STUD FOR WATCHES.

SPECIFICATION forming part of Letters Patent No. 224,227, dated February3, 1880.

Application filed December 11, 1879.

To all whom it may concern:

Be it known that I, EDWARD RIVETT, of Boston, in the county of Sutl'oll;and State of Massachusetts, have invented a new and useful ImprovementinHair-Spring Stud, of which thetollowing is a specification.

The nature of my invention consists in combining with hair-spring stud,which has a kerf extending from its upper end nearly to the lower end,projecting arms which bear on one side of the plate, ih e bearing-pointsbeing near their outer ends. To hold this stud in place, its lower endextends entirely through the plate, and is held by a screw-nut. As theouter ends of the projecting arms reston the plate, any considerableforce exerted by the screw-nut to draw the stud down will cause the armsto incline upward, and thus throw that half of the stud to which theyare attached in toward the other half-that is, the kerf will close upand securely grasp the hairspring.

In the drawings, Figure 1 is a plan of a watch-plate. Fig.2 is averticalsection,showing the stud and a part of the plate. Fig. 3 is a plan,showing the recess in the plate. Fig. 4 is a plan of the stud. Fig. 5 isa perspective view of the stud and its screwaiut.

Let A represent the watch-plate, which is provided with a rectangularsinkage, B, Figs. 2 and 3, and has a hole, I), in the center of thissinkage, which extends entirely through the plate.

The hairspring stud L, Figs. 1, 2, 4, and 5, is made as shown in thedrawings, having a kerf, K, extending nearly through its length, and twoprojecting arms, E E, Figs. 2, 4, and 5. These projecting arms E E areso made,

in connection with the recess in the plate, that their outer ends onlybear upon the plate.

H is a screw-nut, which is attached to the lower end of the stud andserves to hold it firmly in place.

To give more elasticity to the sides 0 U of the stud, l file away aportion of the metal at the points M M, as shown in Fig. 2, immediatelyunder the arms E E.

My hair-spring stud operates as follows: It is inserted in the plate, asshown in Fig. 2, and the screwnut H is turned onto it, but notsufficiently tobring any strain upon the arms E E. Now the hair-springis inserted in the kert' K, and the nut H is turned on more firmly. soas to draw the stud down. This action will have a tendency to force theends of the arms E E upward, which action willcause the parts 0 and (Jto incline toward each other, and thus close up the kerf and firmlygrasp the hair-sprin The recess B in the plate A (see Fig. 3) receivesthe projections E E, and thus prevents the stud from turning.

I claim 1. In a clock or watch, the kerfed stud L, having the projectingarms E E and screwnut H, operating together substantially as described,and for the purpose set forth.

2. In a clock or watch, the kerfed stud L, having projecting arms E E,in combination with the recessed plate A 13, substantially as described,and for the purpose set forth.

EDWARD RIVETT.

Witnesscs FRANK G. PARKER, ERNEST N. BoYDEN.

